Refrigeration apparatus

ABSTRACT

Refrigeration apparatus for supplying chilled water at utility quantities including a refrigerant compressor, a plurality of evaporators and a plurality of condensers. A group of the evaporators are interconnected to form a single-flow path for the water flowing in heat transfer relationship with the refrigerant of the system. Track means will be disposed beneath the evaporator and means will be mounted on the evaporators so the evaporators are movably supported on the track means.

United States Patent [72] Inventor Howard E. Caswell Dewitt, N.Y. [,21]Appl. No. 810,696 [22] Filed Mar. 26, 1969 {45] Patented June 29, 1971[73] Assignee Carrier Corporation Syracuse, N.(.

[54] REFRIGERATION APPARATUS 1 Claim, 2 Drawing Figs.

[52] U.S. C1 62/448, 62/510 62/297, 62/389, 165/78 [51} Int. Cl F25d19/02 [50] Field of Search 62/510, 297, 448, 389; 165/78 [56] ReferencesCited UNITED STATES PATENTS 115,870 6/1871 Logorce 165/78 2,256,8829/1941 Sebald 165/78 2,266,107 12/1941 Waterfill 1 l 62/510 2,727,364l2/l955 Perez i 1. 62/297 3,067,592 12/1962 McFarlan 62/510 3,210,95710/1965 Rutishauser... 62/448 3,242,686 3/1966 Bowman 62/510 PrimaryExaminer-William .1. Wye Attorneys-Harry G. Martin, Jr. and l. RaymondCurtin FIG! PATENTEU JUN29 19?:

sum 1 BF 2 INVENTOR. HOWARD E. CASWELL.

ATTORNEY.

PATENIED JUN29 l97| SHEET 2 CF 2 FIG. 2

INVENTUR. HOWARD E. CASWELL -44 M4 M REFRIGERATION APPARATUS BACKGROUNDOF THE INVENTION This invention relates to a novel refrigerationapparatus and in particular to such apparatus particularly adaptable foruse where chilled water in utility quantities for air conditioningsimultaneously a considerable number of buildings will be produced.

It has been envisioned that public utility companies will eventuallysupply conditioned water for heating and cooling purposes to extensiveareas similar to the manner in which they now supply electricity andgas.

From a central plant, water mains will run to each and every block,thereby distributing hot or cold water as is required. It is thoughtthat such a service can be provided at a considerably lower cost andwith greater dependability than is possible with present individualheating and cooling systems.

At present, at least one such public utility company is sup plyingchilled water for air-conditioning purposes to a sizable group ofcustomers in an extended area.

To maintain the quantity of conditioned water required for utilityservices, machines of much larger'size, when compared to the machinespresently in use even in large commercial plants, must be utilized. Suchlarge machines might be required to be rated at 50,000 tons. Sincepresent machines are generally limited to a maximum of about 5,000 tons,such a substantial increase in size would create many problems.

If a single unit were to be manufactured with a capacity of up to 50,000tons, a substantial investment in ultra-large machine tools would benecessary. Additionally, severe design distortions would be required inorder to ship the excessively large machines via trucks or railroadcars. Furthermore, spare parts would be costly, and repairs and ordinarymaintenance would probably require a relatively long inoperable period,which would be extremely undesirable when considering the function ofthe machine.

Alternatively to manufacturing single giant units, a number of smaller,standard size chillers may be connected together to supply the quantityof chiller water required for utility purposes. The manner in which aplurality of units may be connected or lashed" together for operation asa single unit is well known to those familiar with the art. However,although such an assembly will alleviate much of the tooling andshipping problems hereinabove discussed, repairs would still be timeconsuming with conventional constructions of condensers and evaporators.

The object of this invention is to alleviate the problems discussedhereinabove by affording novel constructions for refrigeration machinerywhich will make such apparatus especially adaptable for utility plantsor similar large systems wherein a plurality of units will be lashedtogether for joint operation.

SUMMARY OF THE INVENTION The invention herein disclosed pertains to thenovel construction of refrigeration apparatus which will make suchapparatus especially useful in large operations where two or morerefrigeration units will be interconnected for operation as a singleunit."

Generally, two or more large refrigeration compressors will be connectedto operate in parallel. The compressors will discharge high-pressure,high-temperature refrigerant gas through large discharge manifolds to aplurality of condensers. The condensers, in order to save space andreduce piping costs, will preferably be supportably mounted on top ofthe refrigerant evaporators.

Since condensers normally require relatively frequent cleaning, theyshould be positioned so they are easily accessible. To satisfy thisrequirement, the condensers are mounted so their horizontal axes areskewed relative to the horizontal axes of the evaporators. This willpermit ready access to the water boxes of the condensers simply byremoving the end covers thereof. The condensers water lines should beconnected in parallel so that individual condensers may be isolated forrepair or servicing without necessitating a shutdown of the entiresystem. Valves would be provided in the refrigerant supply lines to thecondensers to isolate a condenser that is to be serviced from theoverall refrigerant circuit.

The condensed refrigerant will flow from the condensers to theevaporator upon which a condenser is mounted. A number of theevaporators are preferably connected in series, and two or more seriesof evaporators-will be connected in parallel. Such arrangements willprobably provide maximum heat transfer for most applications. However,the arrangements of the evaporators may be altered if required tomaintain maximum heat transfer. The extra waterside pressure drop causedby connecting the evaporators in series in this arrangement is such asmall percentage of the total distribution pressure drop that it iscompletely practical.

Disposed beneath each of the serially connected evaporator groups willbe track means. The evaporators will be movably supported on the trackmeans by means mounted on the evaporator, such as flanged wheels. Thetrack means and the associated means mounted on the evaporator willfacilitate maintenance and repairs to the evaporators. The track meansshould exceed the total, length of a group of serially connectedevaporators by at least the length of one evaporator.

If an evaporator connected in an intermediate position in a group isrequired to be cleaned or otherwise repaired, it first must bedisconnected from the adjacent evaporators on either end. Next anoverhead crane will lift the entire evaporator structure and deposit iton the length of the unused track means. One section of the remainingevaporators will be slidably moved along the track means to the othersection of evaporators and the two sections will be connected. Withoutthe track means, the evaporators would normally be securely mounted tothe floor or other stationary supporting means. Repairs could not bemade to an evaporator in an intermediate position in a seriallyconnected group of evaporators without shutting down the group for thetotal length of time necessary to effectuate the repair. Alternatively,extensive and costly piping would be required to bypass any evaporatorrequiring repair or cleaning.

The invention disclosed herein will facilitate the repair andmaintenance of a plurality of interconnected refrigeration units and, inaddition, will reduce the costs of making such repairs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of aplurality of refrigeration units interconnected for joint operation, theunits being slidably mounted on track means; and

FIG. 2 is an end view of the refrigeration units mounted on the trackmeans.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,there is illustrated a preferred embodiment of the invention hereindisclosed wherein like numerals will refer to like parts.

The refrigeration apparatus illustrated in the accompanying drawings isdesigned to supply chilled water in quantities sufficient to provide airconditioning to extensive areas. Such an application would be thedistribution of chilled water for airconditioning purposes by a publicutility company, similar to the manner in which such a company suppliesgas or electrici ty.

Specifically, a steam turbine 12 or other power source such as anelectrical motor is connected to simultaneously operate refrigerationcompressors 10 and 11 connected to operate in parallel. It should beunderstood that although the compressors are connected to be drivensimultaneously, it is within the scope of this invention for thecompressors to have individual drives. Additionally, although twocompressors are used in a preferred embodiment, the number ofcompressors can be increased or decreased depending upon therequirements of each installation. Furthermore, it is within the scopeof the in vention for the compressors to operate in series, or inseriesparallel combinations, as is well known in the art.

High-temperature, high-pressure refrigerant gas is discharged from thecompressors l and 11 by lines 13 and 14 into discharge manifolds l and16. The discharge manifolds l5 and 16 are substantially large pipesconnecting the refrigerant compressors to a plurality of refrigerantcondensers. Each of the compressors and 11 supply the high-pressurerefrigerant gas to a plurality or group of condensers. As shown, the twogroups of condensers of the embodiment are connected to operate inparallel. A plurality of smaller conduits 17 connect the dischargemanifolds l5 and 16 to the plurality of refrigerant condensers 18, 18a,18b, 18c, and 19, 19a, 19b, and 190.

The refrigerant gas passes through the condensers in heat transferrelation with a relatively low-temperature medium such as water. Thewater absorbs heat from the refrigerant gas, thereby condensing the gasinto a refrigerant liquid. Main water supply headers 20 and 24 fordelivering water to the condensers are connected to each of thecondensers by relatively small conduits 21. Conduits 21 are connected inparallel in each group of condensers for a reason to be explained morefully hereinafter. Discharge lines 22 from each of the condensersdeliver the warmed heat transfer medium to discharge vheaders 23 and 25.The warmed water is then either cooled for reuse as a heat transfermedium or is discharged entirely from the system.

The liquid refrigerant flows from the condensers to a plurality ofevaporators 26, 26a, 26b, 26c, and 27, 27a, 27b, and 270 through a floatvalve 29 disposed therebetween. The float valves 29 regulate the flow ofliquid refrigerant to the evaporators. It should be understood thateconomizers or other intermediate flash coolers may be utilized in lieuof the float valve 29. Each evaporator comprises a substantiallycylindrical outer shell or housing 41 defining an inner chamber 42.Disposed within the inner chamber 42 are a plurality of tubular means43. The inner surface of the tubular means 43 defines a flow path forone medium flowing through the evaporators. A second flow path for asecond medium is defined by the outer surface of the tubular means 43and the inner surface of the housing 41. The liquid refrigerant willpass through the evaporators, by being directed through one of the flowpaths, in heat transfer relation with a medium to be cooled such aswater, which passes through the evaporators via the other flow path. Theliquid refrigerant will absorb heat from the water, causing therefrigerant to vaporize and the water to be cooled as desired. Thegaseous refrigerant will then be returned to the compressors 10 and 11via evaporator discharge lines 30 connected to the compressor suctionheaders 31 and 33, thus completing the basic refrigeration cycle.

The plurality of evaporators will be divided into several groups. Theevaporators comprising each group of a preferred embodiment will beserially connected via connecting means such as flanged pipes 28. Thewater to be chilled is supplied to the evaporators via evaporator supplyheader 32. The water after having been cooled in the evaporators isdelivered to the areas being served by discharge main 34 which willsupply the water to smaller conduits for eventual delivery to the areasbeing served.

Groups of evaporators will be serially connected as shown so asingle-flow path is provided through each group for the water beingcooled. The water will be progressively cooled as it passes through eachof the evaporators comprising a group. The arrangement will enableextremely large quantities of water to be sufficiently cooled forconditioning the large number of areas being served.

To save piping and foundation costs and reduce the space required forthe refrigeration apparatus, the condensers should be preferably mountedon an associated evaporator. As

is seen in FIG. 2, the condensers can be supportably mounted by meanssuch as beams or supports 35. Preferably, the horizontal axes of thecondensers will be skewed relative to the horizontal axes of theevaporators. This will provide easy access to the water boxes 36 and 37of the condensers. Since condensers are the apparatus that most requiremajor maintenance in a refrigeration cycle, it is a highly desirablefeature of the invention disclosed herein that the condensers be readilyaccessible for such maintenance.

As noted hereinbefore, the water supply and return lines to thecondensers are usually connected in parallel. Thus, by shutting offappropriate refrigerant valves (not shown), any condenser can beisolated when maintenance is required without necessitating the shutdownof an entire group of condensers and evaporators.

As also noted hereinbefore, the refrigeration system shown is designedspecifically for installations requiring large capacities ofconditioning effect. Since it is conceivable that the requirements willincrease, means should be available so that additional apparatus can bereadily added to the system when necessary. Additionally, since theevaporators are serially connected, means should be available toexpedite evaporator repairs, since maintenance to any one evaporatorwill necessitate the shutdown of the group of serially connectedevaporators.

To obtain these desirable characteristics, track means 38 are disposedbeneath each of the evaporator groups. Mounted beneath each of theevaporators and engaging the track means 38 are means such as flangedwheels 39 so the evaporators are movably supported on the track means38. An evaporator at one end of each group, for example evaporators 26and 27, should be firmly held in place by means such as anchor 40 shownin FIG. 2. However, the flanged wheels 39 should be free to rollslightly to accommodate the substantial linear contractions that willoccur due to the quantity of relatively cold water that will be flowingthrough the serially connected evaporators. Additionally, there shouldbe some flexible lengths of piping in the chilled water circuit toaccommodate linear contractions in the piping.

If an evaporator in an intermediate position in a group, for example26b, requires maintenance such as retubing, the flanged piping section28 on either side of the evaporator will first be disconnected.Refrigerant lines to and from the evaporator would be closed off byvalves (not shown). It is of course understood the entire group ofevaporators will have been shut down prior to the commencement of anyrepairs. After appropriate piping, such as the chilled water header 33and the discharge manifold 15 have been disconnected, the connectedevaporators at one end of the evaporator requiring maintenance will bemoved along the track means 38 in the direction of the unanchoredevaporator. The evaporator 26b requiring maintenance can then be liftedas a unit by means such as overhead cranes (not shown). The evaporatorwill be set down on an extra or normally unused portion of track means38 where the required maintenance willbe conducted. The remainingevaporators and condensers will be reassembled along with the pipingthat required disassembly before the evaporator requiring maintenancecould be removed from the group. Thus, any maintenance or repairsrequired for the evaporators of the system will not keep a group ofevaporators shut down for a prolonged period of time. The entire systemwill be reoperating in a minimum amount of time. By utilizing trackmeans 38, a minimal amount of piping need be disassembled before any oneevaporator can be removed from a group for repairs.

While I have described and illustrated a preferred embodiment of myinvention, it should be understood that my invention is not limitedthereto, since it may be otherwise embodied within the scope of thefollowing claims.

lclaim:

l. Refrigeration apparatus comprising:

a. refrigerant compression means having a suction and a discharge side;

b. a plurality of refrigerant condensers;

with the refrigerant of said apparatus;

f. means for supportably mounting each of said condensers on top of anassociated evaporator, the horizontal axis of such condensers being at askew angle relative to the horizontal axis of said cvaporators;

g. track means disposed beneath said evaporators; and

h. means mounted on said cvaporators so said evaporators are movablysupported on said track means.

1. Refrigeration apparatus comprising: a. refrigerant compression meanshaving a suction and a discharge side; b. a plurality of refrigerantcondensers; c. first manifold means connecting the discharge side ofsaid compression means to the inlet of said condensers; d. a pluralityof refrigerant evaporators having water flowing therethrough; e. secondmanifold means connecting at least a part of said plurality ofevaporators to said suction side of said compression means, said part ofsaid evaporators being interconnected to form a single flow path for thewater flowing through said evaporators in heat transfer relationshipwith the refrigerant of said apparatus; f. means for supportablymounting each of said condensers on top of an associated evaporator, thehorizontal axis of such condensers being at a skew angle relative to thehorizontal axis of said evaporators; g. track means disposed beneathsaid evaporators; and h. means mounted on said evaporators so saidevaporators are movably supported on said track means.